Anti-disengagement connect system for a power tool

ABSTRACT

Embodiments are disclosed of an anti-disengagement assembly for minimizing disengagement of an electrical extension cord from a power tool of the type that includes a housing and a motor therein, the assembly including an electrical plug module configured to engage a receptacle of the extension cord, with the plug module being operatively connected to the power tool motor and being mounted in the housing and being biased by at least one spring in a configuration permitting limited movement that reduces the influence of vibration produced by the power tool on the plug module.

BACKGROUND OF THE INVENTION

Electronic devices such as power tools often include an electrical plugmodule for coupling with an electrical extension cord, therebypermitting an operator to use the power tool at locations remote fromthe nearest available electrical outlet. One common configuration forsuch a system is to include the electrical plug module within a recessof the housing such that prongs of the electrical plug module areaccessible to engage the female receptacle disposed on the electricalextension cord. Thus, the electrical extension cord may be coupled tothe recessed electrical plug module, with the coupling being at leastpartially hidden from view and at least partially protected within thepower tool housing from becoming dislodged.

However, nearly all power tools produce some jarring and/or vibration ofthe power tool during operation, which in turn jars and vibrates thecoupling between the electrical plug module and the electrical extensioncord. The jarring/vibration causes the electrical plug module to vibrateat a different frequency than the extension cord. Due to the differentrelative vibration, the electrical plug module and electrical extensioncord may become at least partially if not totally disengaged from oneanother, resulting in a loss of power to the power tool and possiblydamaging the connection due to electrical arcing, interrupting itsoperation and usually aggravating the operator.

A retaining clip may be added, which is attached to the same handle/bodyin which the electric plug module is mounted. When provided, theretaining clip is also configured and arranged to make contact with theextension cord. The retaining clip will thereby transfer to theextension cord the vibration frequency of the handle/body that containsthe plug module. The connection will reduce the effect of relativevibration and help prevent the cord from backing out. However, due tothe wide range of extension cord female plug shapes, the retainer clipmay make the female plug insertion difficult and may aggravate theoperator. In addition, some plug shapes may not be as effective asothers. The elimination of the retainer clip is desirable from anoperator prospective.

In addition, where the power tools are portable, and are releasablycoupled to an extension cord, inadvertent pulling or catching of theextension cord may cause the extension cord to become disengaged. Forexample, operators will frequently though inadvisably handle the powertool by the extension cord, and often times the weight of the power toolitself is greater than the amount of force required to disengage theextension cord from the tool. Other times the extension cord will becomecaught or snagged on a portion of the work surface or other part of theenvironment, and as the operator moves the power tool during operation,the operator inadvertently pulls the power tool away and disengages fromthe extension cord.

SUMMARY OF THE INVENTION

Embodiments of the invention provide an anti-disengagement assembly thatminimizes vibration and disengagement of an electrical extension cordfrom a recessed electrical plug module disposed within a housing of apower tool. In a first preferred embodiment, axial vibration is reducedby a pair of biasing elements, which are disposed at opposing ends ofthe plug module, permitting a range of free movement of the plug module,where the plug module “floats” between the biasing elements. In a secondpreferred embodiment, axial vibration is absorbed by a plug modulehaving a shape that is configured to permit at least limited rotationwithin the housing of the power tool. Additionally, a single biasingmember is preferably provided in the second preferred embodiment tomaintain the position and orientation of the plug module, as well asisolating the plug module from vibration. Still other embodiments of theinvention include an anti-disengagement assembly

DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of an anti-disengagement assemblyaccording to a first preferred embodiment of the invention;

FIG. 2 is a side perspective view of the anti-disengagement assembly ofFIG. 1 illustrated within a half of a power tool housing;

FIG. 3 is an exploded perspective view of the anti-disengagementassembly of FIG. 1;

FIG. 4 is an exploded perspective view of the anti-disengagementassembly of FIG. 1;

FIG. 5 is a side elevation view of an anti-disengagement assemblyaccording to an alternative embodiment of the invention;

FIG. 6 is a side perspective view of the anti-disengagement assembly ofFIG. 5;

FIG. 7 is an exploded perspective view of the anti-disengagementassembly of FIG. 5;

FIG. 8 is a side perspective view of an anti-disengagement assemblyaccording to a second preferred embodiment, illustrated within a half ofa power tool housing;

FIG. 9 is a front elevation view of the anti-disengagement assembly ofFIG. 8;

FIG. 10 is a front perspective view of a tool handle incorporating anexemplary cord retaining system;

FIG. 11 is a bottom view of the tool handle of FIG. 1 shown with anextension cord in place;

FIG. 12 is a left rear projection of a portion of a tool illustrating afourth preferred embodiment of an anti-disengagement assembly; and

FIG. 13 is a side view, partially in section and with portions removedof the fourth preferred embodiment of an anti-disengagement assemblyshown in FIG. 12.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention include an anti-disengagementassembly for minimizing vibration induced disengagement of an electricalextension cord from an electrical plug module of a power tool. Otherembodiments of the invention include an anti-disengagement assembly forminimizing disengagement of an electrical extension cord from anelectrical plug module resulting from both vibration induceddisengagement as well as inadvertent pulling or catching of theextension cord from the electrical plug module.

By providing one or more biasing members in close proximity to the plugmodule, the biasing members absorb tool vibration, thereby permittingmovement of the plug module that is independent of the movement of thetool. In combination with one or more biasing members, other embodimentsmay include a cord retaining system that releasably retains a portion ofthe cord in close proximity to a tool housing to reduce the possibilitythat the extension cord will be inadvertently pulled or snagged. Whileit is contemplated that the invention may be used in connection with anyelectrical device, the preferred embodiments are used in connection withpower tools, either hand held portable such as a circular saw orstationary such as a table saw, for example.

In the first preferred embodiment, opposing biasing members are providedat each end of a plug module, permitting the plug module to “float”between the biasing members. Vibration of the power tool duringoperation is absorbed by the biasing members, providing for the freemovement of the plug module independent of any movement of tool or toolcomponents. Thus, an extension cord will move with the plug module,thereby limiting the impact of tool vibration on the coupling of theplug module and the extension cord.

Turning therefore to FIGS. 1-4, a first preferred embodiment of theanti-disengagement assembly, designated generally at 10, is illustratedwith a portion of a circular saw housing, designated generally at 12, ofthe type that includes a motor (not shown) and a recessed electricalplug module 16 disposed within the housing. While the electrical plugmodule 16 may be configured and arranged pursuant to manufacturingspecifications, the plug module 16 is preferably recessed within ahollow generally cylindrical chamber portion 20 of the housing 12 suchthat prongs 22 of the plug module extend outwardly toward an opening 24in the chamber portion while electrical wires 26 extend oppositely tooperatively connect the plug module to a switch (not shown) whichconnects it to the motor 14.

The housing 12 is typically composed of plastic, such as AcrylonitrileButadiene Styrene (ABS) or glass-filled nylon, and is assembled from twohalves that engage one another in a clam-shell configuration. Asillustrated in FIG. 2, each half of the chamber portion 20 includes aplurality of features that promote engagement and retention of theanti-disengagement assembly 10. The anti-disengagement assemblycorrespondingly includes features that engage the chamber portion 20 ofthe housing 12.

More particularly, the first preferred embodiment anti-disengagementassembly 10 includes the electrical plug module 16, inner and outerbiasing members 28, 30, and inner and outer retaining members 32, 34.Generally, the inner biasing member 28 is configured and arranged tobias the plug module 16 in a first outward direction 36 toward theopening 24 in the chamber portion 20, while the outer biasing member 30is configured and arranged to bias the plug module in a second direction38 opposite that of the first direction. The inner and outer biasingmember 28, 30 and the plug module 16 that is disposed therebetween areretained within the inner and outer retaining members 32, 34.

The plug module 16, as illustrated in FIGS. 1-4, includes a generallycylindrical body 40 having a first outer circumference, and an end plate42 disposed at an inner end of the cylindrical body, wherein the endplate has a second outer circumference that is at least slightly largerthan the first outer circumference. The outer circumference of the endplate 42 is preferably non-uniform, with an arcuate portion 44 around aportion thereof, as well as a pair of generally parallel planar portions46 diametrically opposing one another, and a generally flat bottom edge48. The generally planar portions 46 and the bottom edge 48 areseparated by rounded edges 50.

The inner biasing members 28 and 30 are preferably helical compressionsprings that have a relatively low spring force and small displacementwhich will enable the plug module to float between the springs, and toslightly move responsive to normal forces that are applied when anextension cord is connected to the plug module 16. This enables thesprings to absorb vibration produced by the tool and thereby tend toisolate the plug module 16 from the effects of the vibration. Thediameter of the outer biasing member 30 is larger than that of the innerbiasing member 28, so it is preferred that the wire size or other forcevarying parameter be changed to produce generally equal spring forces ofthe biasing members 28 and 30.

The inside diameter of the outer biasing member 30 is slightly largerthan the outside diameter of the body 40 of the plug module 16 so thatit can be positioned on it. An inner end 52 of the outer biasing member28 then abuts an annular shoulder 53 defined by the end plate 42. Theinner diameter of the inner biasing member 28 is configured to permitpassage of the electrical wires 26, with an outer end 54 of the innerbiasing member 28 abutting the end face of the end plate 42.

The plug module 16 of the first preferred assembly 10 “floats” betweenthe inner and outer biasing members 28, 30, with the inner and outerbiasing members absorbing vibration to at least partially isolate theplug module from being jarred by the vibration. While it is contemplatedthat mechanical features of the housing 12 may be provided to retain theinner and outer biasing member 28 and 30, the assembly 10 includes theinner and outer retaining members 32, 34, which when assembled to oneanother, at least partially enclose the inner and outer biasing membersand the floating plug module 16.

Specifically, as illustrated in FIG. 1, the inner retaining member 32 ispreferably arcuate in shape, with a generally flat end portion 56 havingan orifice 58 to permit passage of the electrical wires 26. Sideportions 60 extend from the end portion 56, which may optionally includea window 62 to reduce the overall size of the inner retaining member 32.An inner end 64 of the inner biasing member 28 is configured to abut aninside surface of the end portion 56, while an outside surface of theend portion 56 preferably abuts a pair of ribs 66 extending upwardlyfrom the housing 12.

The outer retaining member 34 is preferably configured to include anouter ring 68 from which curved side members 70 extend rearwardly. Aswith the inner retaining member 32, one of the side members 70 mayoptionally include a window 72 to reduce the overall size of the outerretaining member 34. An inner circumference of the outer ring 68 isconfigured to permit passage of the prongs 22, and an inner surface ofthe outer ring preferably includes an annular shoulder 74 configured toengage and retain the outer end 76 of the outer biasing member 30. Apair of diametrically opposed, shelves 78 are preferably disposed on theouter ring 68 to engage a correspondingly configured shoulder 80 thatextends inward from the housing 12 and prevents rotation of theretaining member 34 relative to the housing.

To promote “floating” of the plug module 16 between the inner and outerbiasing members 28, 30, the inner and outer retaining members 32, 34 areconfigured to engage one another. While the assembly 10 contemplatesnumerous engagement mechanisms, one exemplary engagement is a snap-fitengagement, and is illustrated in FIG. 2. To this end, the outer end ofthe inner retaining member 32 preferably includes a generallyrectangular recess 82 at each of the side portions 60, while the innerend of the outer retaining member 34 includes correspondingly configuredlocking extensions 84 on each of the side members 70. In addition, themedial ends of both the inner and outer retaining members 32, 34 mayinclude correspondingly configured arcuate shelves 85 a, 85 b, whichpromote alignment and engagement of the retaining members to oneanother.

Thus, when assembled, the anti-disengagement assembly 10 includes theinner and outer retaining members 32, 34 connected to one another, withthe plug module 16 and inner and outer biasing members 28, 30 disposedbetween them. The assembly 10 is retained within the chamber portion 20of the housing 12 with the outside surface of the end portion 56 of theinner retaining member 32 abutting the ribs 66 of the housing, while theshelves 78 of the outer ring 68 engage the annular ring 80. In thismanner, the assembly 10 is disposed within the housing 12, with the plugmodule disposed so as to “float” between the first and second biasingmembers 28, 30.

The assembly 10 may be modified in a variety of ways. For example, therespective structures of the inner and outer retaining members 32, 34may be modified to provide alternative means of engaging the retainingmembers to one another, as well as within the housing 12. As illustratedin FIGS. 5-7, the inner retaining member 32 may be configured to includea pair of radial extensions 86 that extend in opposite directions. Theradial extensions 86 engage portions of the chamber portion 20 toenhance retention of the inner retaining member 32 within the housing12. For example, as illustrated in FIG. 5, one radial extension 86engages a space between a C-shaped projection 88 and a side wall 89 ofthe housing 12, while the other radial extension abuts a rib 90.

Additionally, the side portions 60 may be extended in length, andinstead of recesses, may instead include generally rectangularextensions 92 at the ends thereof, where each of the rectangularextensions includes a wedge-shaped locking member 94 at its underside.Similarly, the side members 70 of the outer retaining member 34 may beshortened, and instead of including extensions, may include generallyrectangular depressions 96 configured to frictionally receive therectangular extensions. Disposed within each of the rectangulardepressions 96 is a rectangular window 98 configured to lockinglyreceive a respective one of the locking members 94 therein. Thus, theinner and outer retaining members 32, 34 may be altered and still beconfigured to engage one another, as well as to promote retention of theassembly 10 within the housing 12.

A second preferred embodiment, designated generally at 100 in FIG. 8,includes features to reduce the vibrational impact on the couplingbetween an extension cord (not shown) and a plug module 102 duringoperation of a power tool. However, while the plug module 16 of theassembly 10 is configured to float between the two biasing members 28,30, the assembly 100 of the second preferred embodiment 100 isconfigured to absorb vibration by at least partially rotating the plugmodule 102 in response to the vibration.

To this end, the plug module 102 of the second preferred assembly 100is-configured to be at least partially rounded to promote rotationwithin a chamber portion 20′ of the housing 12. As illustrated in FIGS.8 and 9, the plug module 102 includes a generally spherical body 104with an annular collar 106 disposed at an end thereof, wherein prongs108 of the plug module extend from a generally planar end 108 defined bythe annular collar. A second end 112 of the spherical body 104 oppositethe annular collar 106 is also generally flat, with one or moreelectrical wires 114 extending from it.

Preferably, a single biasing member 116 is provided to bias the plugmodule 102 in an outward direction. The inclusion of the biasing member116 is advantageous in that compression and expansion of the biasingmember promotes absorption of vibration by the plug module 102. Thebiasing member 116 may also promote maintenance of the position andorientation of the plug module 102 within the chamber 20. The preferredbiasing member 116 is a helical coil.

The chamber portion 20 of the housing 12 is correspondingly configuredto both retain the second preferred assembly 100, as well as to bias theplug module 102 in an outward direction. More particularly, an annularring 118 extends radially inwardly from an inner circumference of thechamber portion 20. In this manner, the inner circumference is reducedat a predetermined location and is sized to permit passage of theannular collar 106, but prevents passage of a majority of the sphericalbody 104. Thus, a portion of the spherical body 104 is in abutment withthe annular ring 118 of the housing 12.

A generally circular plate 120 is disposed at an inner end of thechamber portion 20, and an inner end 124 of the biasing member 116 abutsan outer surface 123 of the circular plate. An outer end 124 of thebiasing member 116 abuts the second end 112 of the plug module 102. Inaddition, guide ribs 126 extend from the chamber portion 20 to promotemaintenance of the orientation of the biasing member 116 within thechamber portion 20, and to help reduce distortion of the biasing member116 as it is compressed.

Thus, when assembled, the second preferred assembly 100 includes thebiasing member 116 biasing the plug module 102 outwardly. The assembly100 is retained at an outer end by the annular ring 118, and at an innerend by the circular plate 120. The biasing member 116 absorbs the axialvibration of the spherical body 104, while permitting compressionsufficient to allow the spherical body to rotate in both clockwise andcounterclockwise directions 128, 130 relative to the axial lengthwisedirection of the biasing member 116, thereby maintaining a position ofthe plug module 102 and its engagement with the extension cord.

A third preferred embodiment of the invention is especially advantageousin applications involving portable power tools, and includes both ananti-vibration assembly as well as a cord retaining system. While theanti-vibration assembly of either the first or second preferredembodiment minimize vibration induced disengagement of an extension cordfrom a plug module, a portion of the extension cord external to thechamber 20 of the housing 12 is susceptible to being pulled or snaggedduring movement of the tool during operation. Accordingly, the thirdpreferred embodiment includes a cord retaining system for releasablyretaining a portion of the cord in close proximity to the tool housing12 to reduce the possibility that the extension cord will beinadvertently pulled or snagged and subsequently result in disengagementof the extension cord from the plug module.

While the invention contemplates that a variety of configurations willsuffice to provide retention of the extension cord, an exemplary cordretaining system is illustrated in FIGS. 10 and 11. This cord retainingsystem is provided by U.S. patent application Ser. No. 10/790,361, whichpublished Aug. 26, 2004 as Publication No. US-2004-0166730-A1, entitled,Extension Cord Retention and Plug Retention System, filed Mar. 1, 2004,and is hereby incorporated by reference. A power tool generallydesignated at 132 is shown fragmentarily, and is contemplated as beingany one of a group of commonly known portable electric power tools,including, but not limited to drills, hammer drills, sanders, grinders,circular saws, reciprocating saws, routers, power fastener drivers,garden weed trimmers, leaf blowers and the like, all being commercial orhomeowner-type power tools commonly used with an extension cord,generally designated 134 (best seen in FIG. 11). The length of the cord134 may vary, as well as its gauge or diameter and still be suitable foruse with the present invention. However, for commercial applications,the extension cord 134 will typically be made of 10, 12 or 14 gaugewires in a cord.

The exemplary cord retaining system, generally designated 136, issecured to a handle portion of the housing 12 by being integrally moldedthereto, or alternatively adhered by chemical adhesives or threadedfasteners. Two main components make up the cord retaining system 136,which are a cord capture formation 138 and a cord channel 140. The cordcapture formation 138 is configured to retain the extension cord 134disposed on the housing 12, and the cord channel 140 is disposed on anoutside surface of the housing and is configured for supporting a loopof the cord substantially along an arc defined by the loop. The cordcapture formation 138 is configured for retaining the extension cord 134at two or more points of contact 142, 144 (FIG. 11), with a loop portion146 of the cord formed between the two points. The cord channel 140receives and supports an apex 148 of the loop portion 146.

More specifically, the cord capture formation 138 is configured todefine an enclosed space 150 when attached to the housing 12. Thus, thecord capture formation 138 may define a circular, oval, free form orother preferably non-cornered shape on its own or using a portion 152 ofthe housing 12. A non-cornered shape is preferred to avoid sharp edgeswhich may cause wear or stress on the extension cord 134. Further, thecord capture formation 138 is configured for maintaining an orientationof the cord 134 that prevents bends and kinks in the cord when the cordis retained in the system 136.

A fourth embodiment of the present invention is shown in FIGS. 12 and13, in a reciprocating saw having a motor 149 and a handle portion 151with a trigger 153 that is operatively connected to a switch 154, thathas electrical conductors 156 that are part of a cord 158 that extendsto a plug module, indicated generally at 160. The plug module 160 has agenerally cylindrical outer portion 162 that surrounds two electricalprongs 164 and a ground prong 166, to which an extension cord may beconnected. It should be understood that the plug module 160 may beconfigured to have only the two electrical prongs 164 in someapplications. A cutout 168 in the upper part of the outer portion 162 isprovided to give a user a visual indication of whether the extensioncord is fully plugged into the plug module 160. The plug module 160 hasan enlarged annular ring 170 that defines a transverse shoulder 172 anda smaller diameter rear portion 174 that merges with a conical portion176 and a small cylindrical portion 178 which connects to the cord 158.It should also be understood that while the embodiment shown anddescribed above is preferably molded as a single unit, an alternativeconfiguration may employ a simple off the shelf electrical plug and cordthat is supported by a retaining member structure (broadly similar tothe retaining members 32 and 34 shown in FIG. 1) that would float withinthe rubber spring 180. Such an alternative configuration retainingmember structure could have a generally cylindrical outer portion with acutout similar to the cylindrical outer portion 162 having the cutout168.

An annular rubber spring, indicated generally at 180, is provided andhas a flat annular base portion 182 that fits within an annular slot 184defined by the housing 150. In this regard, the housing is preferablymade of a hard durable plastic or plastic like material and is formed bytwo mating clamshell portions. The slot 184 is preferably formed in eachof the clamshell portions so that the rubber spring 180 can be placed inthe slot 184 prior to combining the housing portions together which willsecurely hold the spring captive in the slot 184. The spring 180 has twocorrugated portions 186 and 188, the latter of which merges into acylindrical portion 190 that is sized to snugly fit on the cylindricalportion 174 and to bear against the shoulder 172. However, an additionalnumber of corrugations may also be provided, if desired.

The spring is preferably compressed, i.e., the plug module 160 is pulledto the right as shown in FIG. 13. The compression is achieved by a cordclamp 192 that compresses the cord 158 against a support surface whentwo screws 194 are tightened. Of course the cord 158 needs to be pulledto the right so as to compress the spring 180 before the cord clamp 192is tightened. The compression of the spring 180 creates a force appliedto the plug module 160 tending to straighten it out if pulled to theside by an extension cord that is plugged into the plug module 160. Thecombination of the flexible cord 158 and rubber spring 180 isolatesvibration that is generated by the tool and reduces the likelihood thatthe extension cord will separate from the plug module 160. Analternative configuration can be used which eliminates the compressionon the spring. In that configuration the cord is not pulled to the rightto place the spring 180 in compression before it is clamped by cordclamp 192 and the rubber spring 180 would be able to move more freely,which may increase the isolation from vibration generated by the tool.

While various embodiments of the present invention have been shown anddescribed, it should be understood that other modifications,substitutions and alternatives are apparent to one of ordinary skill inthe art. Such modifications, substitutions and alternatives can be madewithout departing from the spirit and scope of the invention, whichshould be determined from the appended claims.

Various features of the invention are set forth in the following claims.

1. A power tool assembly for coupling with an electrical extension cordhaving a receptacle portion to minimize vibration and disengagement ofthe electrical extension cord from a power tool that has a housing, amotor and a motor switch, said assembly comprising: a plug module havinga prong configuration for connecting with the receptacle portion of theextension cord and an integral flexible cord for operative connection tothe motor switch; a hollow rubber-like spring mounted in the housing andbeing configured to retain said plug module.
 2. A power tool assembly asdefined in claim 1 wherein said rubber-like spring comprises a generallycylindrical configuration with an inner end that is retained by saidhousing and an outer end that includes a corrugated portion and acylindrical out end that engages an inwardly directed annular flange. 3.A power tool assembly as defined in claim 2 wherein said corrugatedportion comprises at least two annular corrugations, said corrugationspermitting at least axial movement of said plug module relative to thehousing.
 4. A power tool assembly as defined in claim 3 wherein saidcorrugations hold said plug module in a predetermined orientationrelative to the housing, said corrugations permitting changing of saidpredetermined orientation.
 5. A power tool assembly as defined in claim1 wherein said plug module has a cylindrical extension that extendsoutwardly to the outer end portions of said prongs, said extensionincluding a cutout that enables a user to view the connection of thereceptacle portion and the prongs and determine whether the extensioncord is fully plugged into the plug module.
 6. A power tool assembly asdefined in claim 1 further comprising a cord clamp for clamping the cordto the housing so that the plug module cannot extend away from thehousing when it is in a clamped condition.
 7. A power tool assembly asdefined in claim 6 wherein the cord is pulled inwardly to pull the plugmodule inwardly before the cord clamp is tightened to a clampedcondition.
 8. A power tool assembly as defined in claim 2 wherein thehousing has an annular recess adjacent said rubber-like spring, saidinner end of said spring having a outer transverse annular flange thatfits within said housing annular recess.
 9. A power tool assembly forcoupling with an electrical extension cord having a receptacle portionto minimize vibration and disengagement of the electrical extension cordfrom a power tool that has a motor and a motor switch, said assemblycomprising: a tool housing for containing the motor therein; a plugmodule having a generally cylindrical overall configuration and a firstend portion with a prong configuration for connecting with thereceptacle portion of the extension cord; a flexible electric cordconnected to said plug module and to said prong configuration thereof,said cord extending from a second opposite end portion of said plugmodule and being operatively connected to the motor switch; a flexiblespring-like mounting assembly retained by said housing and holding saidplug module with sufficient force to hold said plug module at apredetermined orientation, but permits at least limited transversemovement of the plug module in said mounting assembly for minimizingvibration of an electrical plug module.
 10. A power tool assembly asdefined in claim 9 wherein said flexible spring-like mounting assemblycomprises a generally cylindrical configuration with an inner end thatis retained by said housing and an outer end that includes a corrugatedportion and a cylindrical out end that engages an inwardly directedannular flange.
 11. A power tool assembly as defined in claim 10 whereinsaid corrugated portion comprises at least two annular corrugations,said corrugations permitting at least axial movement of said plug modulerelative to the housing.
 12. A power tool assembly as defined in claim11 wherein said corrugations hold said plug module in a predeterminedorientation relative to the housing, said corrugations permittingchanging of said predetermined orientation.
 13. A power tool assembly asdefined in claim 9 wherein said plug module has a cylindrical extensionthat extends outwardly to the outer end portions of said prongs, saidextension including a cutout that enables a user to view the connectionof the receptacle portion and the prongs and determine whether theextension cord is fully plugged into the plug module.
 14. A power toolassembly as defined in claim 9 further comprising a cord clamp forclamping the cord to the housing so that the plug module cannot extendaway from the housing when it is in a clamped condition.
 15. A powertool assembly as defined in claim 10 wherein the housing has an annularrecess adjacent said flexible spring-like mounting assembly, said innerend of said mounting assembly having a outer transverse annular flangethat fits within said housing annular recess.
 16. A method of increasingthe holding force applied to power tool assembly for coupling with anelectrical extension cord having a receptacle portion to minimizevibration and disengagement of the electrical extension cord from apower tool that has a housing, a motor and a motor switch, and whereinthe power tool assembly a plug module having a prong configuration forconnecting with the receptacle portion of the extension cord and anintegral flexible plug module cord for operative connection to the motorswitch, a cord clamp for clamping the cord to the housing so that theplug module cannot extend away from the housing when it is in a clampedcondition, a hollow rubber-like spring mounted in the housing and beingconfigured to retain said plug module, said method comprising pullingthe plug module cord inwardly so as to pull the plug module inwardly;and tightening the cord clamp.